import { fromJS } from 'immutable';
import * as constants from './constants'
const defaultState = fromJS({
  topicList:[],
  articleList:[],
  recommendList:[],
  articlePage:1,
  showScroll:false
});

const changehomeData= (state,action) =>{
  return state.merge({
    topicList:fromJS(action.topicList),
    articleList:fromJS(action.articleList),
    recommendList:fromJS(action.recommendList)
  })
}

const addArticleList =  (state,action) =>{
  return state.merge({
    'articleList':state.get('articleList').concat(action.list),
    'articlePage':action.nextPage
  })
}

export default (state = defaultState,action) =>{
    switch(action.type){
      case constants.CHANGE_HOME_DATA:
      return  changehomeData(state,action);
      case constants.ADD_ARTICLE_LIST:
      return addArticleList (state,action);
      case constants.TOGGLE_SCROLL_TOP:
      return state.set('showScroll',action.show);
      //concat 方法去追加内容
      //console.log(action)
        default:
          return state;
    }
}